Book Image

Learn PostgreSQL - Second Edition

By : Luca Ferrari, Enrico Pirozzi
1 (2)
Book Image

Learn PostgreSQL - Second Edition

1 (2)
By: Luca Ferrari, Enrico Pirozzi

Overview of this book

The latest edition of this PostgreSQL book will help you to start using PostgreSQL from absolute scratch, helping you to quickly understand the internal workings of the database. With a structured approach and practical examples, go on a journey that covers the basics, from SQL statements and how to run server-side programs, to configuring, managing, securing, and optimizing database performance. This new edition will not only help you get to grips with all the recent changes within the PostgreSQL ecosystem but will also dig deeper into concepts like partitioning and replication with a fresh set of examples. The book is also equipped with Docker images for each chapter which makes the learning experience faster and easier. Starting with the absolute basics of databases, the book sails through to advanced concepts like window functions, logging, auditing, extending the database, configuration, partitioning, and replication. It will also help you seamlessly migrate your existing database system to PostgreSQL and contains a dedicated chapter on disaster recovery. Each chapter ends with practice questions to test your learning at regular intervals. By the end of this book, you will be able to install, configure, manage, and develop applications against a PostgreSQL database.
Table of Contents (22 chapters)
20
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21
Index

Creating and managing databases

In this section, we will start by creating our first database, then we will learn how to delete a database and, finally, how to create a new database from an existing one. We will also analyze the point of view of the DBA. We will see what happens behind the scenes when we create a new database and learn some basic functions useful to the DBA to get an idea of the real size of the databases.

Let’s see how to create a database from scratch and what happens behind the scenes when a database is created.

Creating a database

To create a database named databasename from scratch, you will need to execute this simple statement:

CREATE DATABASE databasename;

SQL is a case-insensitive language, so we can write all the commands with uppercase or lowercase letters.

Now, let’s see what happens behind the scenes when we create a new database. PostgreSQL performs the following steps:

  1. Makes a physical copy...